City Administrator Steve Diers says officials are researching the proposal.

The anti-drug group SoFar proposed the plan. Group member Charley Thomson says the requirement would be part of the group’s effort to reduce drug use and encourage drug users to seek treatment.

Rita Bettis, legal director of the American Civil Liberties Union of Iowa, says her group would need to research the proposals but that such ordinances often are “housing discrimination dressed up as a crime-fighting tool.”